Binding structures of SERF1a with NT17-polyQ peptides of huntingtin exon 1 revealed by SEC-SWAXS, NMR and molecular simulation.

Lin TC, Shih O, Tsai TY, Yeh YQ, Liao KF, Mansel BW, Shiu YJ, Chang CF, Su AC, Chen YR, Jeng US, IUCrJ (2024) Europe PMC

SASDVP5 – HTT0 peptide

HTT0
MWexperimental 10 kDa
MWexpected 4 kDa
VPorod 4 nm3
log I(s) 8.96×10-3 8.96×10-4 8.96×10-5 8.96×10-6
HTT0 small angle scattering data  s, nm-1
ln I(s)
HTT0 Guinier plot ln 8.96×10-3 Rg: 1.5 nm 0 (1.5 nm)-2 s2
(sRg)2I(s)/I(0)
HTT0 Kratky plot 1.104 0 3 sRg
Dmax: 6 nm

Data validation


Fits and models


log I(s)
 s, nm-1
HTT0 ROSETTA model

Synchrotron SAXS data from solutions of HTT0 peptide in sodium phosphate buffer, pH 7.4 were collected on the TPS13A beam line at the NSRRC (Hsinchu, Taiwan) using a Eiger X 1M & 9M detector at a sample-detector distance of 2.5 m and at a wavelength of λ = 0.08265 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). In-line size-exclusion chromatography (SEC) SAS was employed. The SEC parameters were as follows: A 70.00 μl sample at 10 mg/ml was injected at a 0.35 ml/min flow rate onto a Agilent Bio SEC-3, 300 Å column at 10°C. 10 successive 2 second frames were collected. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.

The sodium phosphate buffer solution contains 480 μL of 10 mM PB, pH 7.4, 16.5 μL of 100 mM NaOH, and 10 μL of 1% trifluoroacetic acid (TFA).

HTT0
Mol. type   Protein
Organism   synthetic construct
Olig. state   Monomer
Mon. MW   4.0 kDa
Sequence   FASTA